1. Field of the Invention
The present invention relates to a magnetic material that can be used primarily as the magnetic core of a coil, inductor, etc., as well as a coil component that uses such magnetic material.
2. Description of the Related Art
Coil components such as inductors, choke coils and transformers (so-called “inductance components”) have a magnetic material and a coil formed inside or on the surface of the magnetic material. For the magnetic material, Ni—Cu—Zn and other ferrites are generally used.
In recent years, there has been a demand for coil components of this type offering electrical current amplification (i.e., higher rated current) and, to meet this demand, switching the material for their magnetic body from conventional ferrites to Fe—Cr—Si alloy is being examined (refer to Patent Literature 1). Fe—Cr—Si alloy and Fe—Al—Si alloy are characterized by a higher saturated magnetic flux density than those of ferrites, but significantly lower volume resistivity compared to those of conventional ferrites.
Patent Literature 1 discloses a method for manufacturing a magnetic body for coil components of the laminated type, which comprises laminating a magnetic layer formed by a magnetic paste containing Fe—Cr—Si alloy grains as well as a glass component, with a conductive pattern, baking the laminate in a nitrogen ambience (reducing ambience), and then impregnating the baked laminate with a thermo-setting resin.
However, the manufacturing method described in Patent Literature 1 allows the glass component contained in the magnetic paste to remain in the magnetic body, and this glass component in the magnetic body causes the volume ratio of Fe—Cr—Si alloy grains to drop, which in turn reduces the saturated magnetic flux density of the component itself.
In the meantime, a powder-compacted magnetic core formed by mixing in a binder is known for use with inductors that use a metal magnetic body. However, general powder-compacted magnetic cores cannot be directly connected to electrodes due to their low insulation resistance.
Any discussion of problems and solutions involved in the related art has been included in this disclosure solely for the purposes of providing a context for the present invention, and should not be taken as an admission that any or all of the discussion were known at the time the invention was made.
Patent Literature
[Patent Literature 1] Japanese Patent Laid-open No. 2007-027354